1. Field of the Invention
This invention relates generally to high pressure sprayers and, more specifically, to high pressure sprayers having multiple nozzles and an indexing assembly which allows the operator to select the appropriate nozzle without shutting off the high pressure fluid to the sprayer.
2. Description of the Prior Art.
The concept of sprayers with plural indexable nozzles are well known as indicated by the Piggott U.S. Pat. No. 3,516,611 and the Bruggeman U.S. Pat. No. 3,377,028. However, these prior art sprayers have serious shortcomings which makes them difficult to use, and in some cases, hazardous to use. One of the problems with prior art high pressure indexable sprayers is that for the operator to index, i.e., select a particular nozzle, the high pressure fluid must be shut off before indexing. If the high pressure fluid is not shut off, the seals within the sprayer will be ruined during the indexing.
The cause of the indexing problem with high pressure fluid is that the high pressure fluid acting on one side of the seal, partially displaces the seal from its required total confinement for indexing. Consequently, indexing results in a pinching, cutting or total destruction of the seal as the nozzle is indexed, i.e., rotated within the sprayer head. To avoid this problem, most commercial high pressure sprayers carry warnings such as "index with pressure off". Even so, indexing under pressure, whether intentional or accidental, is the most common cause of seal failure in indexing sprayers. Not only is seal destruction a problem but the destructive force of a high pressure fluid stream which may be under pressures as high as 1000 psi., can be hazardous to an operator should the operator accidently come in contact with the high pressure stream of fluid. Consequently, some indexing sprayers have provided bleed ports so that in the event of seal failure, high pressure fluid is directed away from the operator.
The present invention provides a solution to the above problem by providing an indexable sprayer which can be safely indexed even though under high fluid pressures, without fear of the sprayer seals being damaged by indexing while under high fluid pressure. The present sprayer is also small and compact making it convenient to use.